Inner membrane efflux components are responsible for beta-lactam specificity of multidrug efflux pumps in Pseudomonas aeruginosa

Research was conducted to test whether the outer membrane OprM protein influences beta-lactam recognition and efflux in Pseudomonas aeruginosa. The oprM gene was cloned on a SphI fragment into a derivative called pXZL01 while the MexCD-OprM efflux system was constructed and analyzed for reconstitution of efflux activity. Results showed that the efflux components are highly homologous and are characterized by an integral cytoplasmic membrane component, a linker protein and an outer membrane protein.